Last updated October 16, 2026
Knowing how to prevent pavers from shifting comes down to three things we get right on every Phoenix install: the base, the edges, and the joints. After building paver patios, driveways, and pool decks across the Valley since 2012, we have seen exactly what makes a field move, and almost all of it traces back to shortcuts taken below the surface. Here is what causes shifting in our caliche and monsoon climate, and how to stop it before it starts.
Why do pavers shift in the first place?
Pavers do not move on their own. They shift because something under or around them failed. The four usual culprits in Phoenix are a base that was too shallow or never properly compacted, a perimeter with no edge restraint to hold the field together, joint sand that washed out or was never the right kind, and monsoon runoff eroding the bedding from below. Ants and weeds make it worse by pushing sand up and out of the joints. The table below maps each cause to what you tend to see in the yard and how we prevent it.
| Why pavers shift | What it looks like | How to prevent it |
|---|---|---|
| Weak or shallow base | Dips, low spots, rutting under load | Excavate to depth, compact aggregate base in lifts |
| No edge restraint | Field spreads outward, perimeter joints open up | Install rigid edge restraint spiked into the base |
| Failed or washed-out joint sand | Loose, rocking pavers, widening joints | Sweep in polymeric sand, re-sand over time as needed |
| Monsoon erosion, poor drainage | Sunken areas after storms, washed-out bedding | Grade for runoff, keep proper slope, compact the base |
| Ants and weeds in the joints | Sand pushed to the surface, pavers loosen | Polymeric sand, optional sealer to help hold the joint |
How deep should a paver base be in Phoenix?
The base is where a paver job lives or dies, and in our soil it has to do more than it would in a milder climate. We excavate to the right depth, then build a compacted aggregate base in lifts, generally around four to six inches for patios and walkways and deeper, often eight inches or more, for driveways that carry vehicle weight. Each lift is compacted before the next goes down, so the whole thing behaves like one solid pad instead of loose rock. Phoenix adds a wrinkle: caliche, the cement-hard calcium layer under much of the Valley, sheds water instead of absorbing it, so a base that is too thin lets monsoon moisture move the ground underneath and the pavers ride along with it. A deep, properly compacted base is the single biggest reason a paver field stays flat for 25 years or more instead of dipping in three.
Do I really need edge restraints on pavers?
Yes, and skipping them is one of the most common reasons a field spreads. Pavers are not glued down. They rely on tight joints and a locked perimeter to stay put. Without a rigid edge restraint spiked into the base along every open edge, the outer pavers slowly creep outward, joints open up, and the field loses its lock from the edges in. We run edge restraint around patios, along walkway sides, and around pool-deck pavers. To be clear, Solterra builds the hardscape around your existing pool, not the pool itself, but the deck and coping still need that restrained edge so they do not wander toward the water. On driveways the edge detail matters even more, because vehicle loads constantly push pavers sideways.
How does polymeric sand keep pavers from moving?
Once pavers are set, the joints between them are what lock the surface into a single interlocking field, and the sand in those joints is doing real structural work. We sweep in polymeric sand, which contains a binder that hardens when it is activated with water, so it resists washing out in monsoon downpours and holds up far better than plain mason sand. Hardened joints also resist the two things that quietly loosen a field in the desert: ants tunneling sand up to the surface, and weeds rooting in the gaps. Over the years some re-sanding may be needed as sand naturally wears, and we handle that as part of paver maintenance. An optional sealer on top adds stain resistance and helps keep the joint sand in place, though it is a look-and-protection choice, not a structural requirement.
Can you fix pavers that have already shifted?
Almost always, yes, and this is one of the real advantages of pavers over a poured slab. Because every unit is individual, a shifted or sunken area can be lifted, the base underneath re-compacted or regraded, and the same pavers reset, rather than tearing out and repouring concrete. We start by finding why it moved: if the base was never deep enough or the edge restraint failed, simply resetting the pavers would just let them shift again, so we fix the cause first. Low spots that pool water after a storm usually mean the base needs regrading for drainage. Spreading edges mean new restraint. Loose, rocking pavers usually just need the joints cleaned out and re-sanded. On older installs we can also reset, re-sand, and seal a tired field so it looks and performs close to new.
